PDFs have a tendency to balloon in size. A resume with a few high-res images easily hits 20MB. A scanned contract? 50MB+. When you need to email a file or upload it to a form, size limits become a real problem.
Most online PDF tools solve this by uploading your file to their server, compressing it, and sending it back. It's convenient, but it means your sensitive documents — contracts, resumes, financial records — leave your device and land on someone else's cloud.
In this post, I'll show you how to compress PDFs without ever uploading them to a server, including a browser-based approach I built for exactly this problem.
Method 1: Built-in OS Tools (Quick but Limited)
Windows
